1. Field of the Invention
The present invention generally relates to optics and, more particularly, to the alignment of lenses that are suitable for use with miniature cameras.
2. Related Art
Digital cameras typically use one or more lenses to provide focused or zoomed images to an imager. In order for the imager to obtain accurate images, it is important that the lenses be properly aligned with the imager. In particular, if lenses are skewed in one or more degrees of rotational freedom or translational freedom, light may not be properly focused on the imager. This can result in images appearing off centered or distorted on the imager.
Manufacturers frequently rely on camera components to be manufactured within sufficiently small tolerances (for example, within approximately 0.025 mm) such that when the components are assembled, lenses are sufficiently aligned to provide satisfactory image quality on an imager. Unfortunately, optical components may not always be available within particular desired tolerances. The accumulation of variations in optical component characteristics, dimensions, and tolerances can result in misalignment of lenses.
In addition, even when lenses are initially properly aligned with an imager, they may become misaligned as a result of impacts received by the digital camera. As a result, relying on manufacturing tolerances and accurate assembly alone can still lead to misalignment of lenses over time. Also, miniature cameras are generally unable to provide meaningful image stabilization. For example, if lenses experience lateral movement in relation to the imager, conventional miniature cameras typically cannot re-align the lenses in relation to the imager to compensate for such anomalies.
Accordingly, there is a need for an improved approach to lens alignment that overcomes the deficiencies in prior approaches as discussed above. In particular, there is a need to provide an improved lens alignment approach that provides for reliable alignment of one or more lenses when employed in personal electronic devices such as miniature digital cameras.